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A291747
Nonprimes of the form 7*k + 1.
2
1, 8, 15, 22, 36, 50, 57, 64, 78, 85, 92, 99, 106, 120, 134, 141, 148, 155, 162, 169, 176, 183, 190, 204, 218, 225, 232, 246, 253, 260, 267, 274, 288, 295, 302, 309, 316, 323, 330, 344, 351, 358, 365, 372, 386, 393, 400, 407, 414, 428, 435, 442, 456, 470, 477, 484, 498
OFFSET
1,2
COMMENTS
Subsequence of A018252.
MATHEMATICA
DeleteCases[7 Range[0, 200] + 1, _?PrimeQ]
PROG
(Magma) [n: n in [1..500 by 7] | not IsPrime(n)];
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Aug 31 2017
STATUS
approved